#!/bin/bash
function showNetSpeed {
	eth='ens33'
	RXpre=$(cat /proc/net/dev | grep $eth | tr : " " | awk '{print $2}')
	TXpre=$(cat /proc/net/dev | grep $eth | tr : " " | awk '{print $10}')
	sleep 1
	RXnext=$(cat /proc/net/dev | grep $eth | tr : " " | awk '{print $2}')
	TXnext=$(cat /proc/net/dev | grep $eth | tr : " " | awk '{print $10}')
	clear
	echo  -e  "\t RX `date +%k:%M:%S` TX"
	RX=$((${RXnext}-${RXpre}))
	TX=$((${TXnext}-${TXpre}))
	  
	if [[ $RX -lt 1024 ]];then
	RX="${RX}B/s"
	elif [[ $RX -gt 1048576 ]];then
	RX=$(echo $RX | awk '{print $1/1048576 "MB/s"}')
	else
	RX=$(echo $RX | awk '{print $1/1024 "KB/s"}')
	fi
	  
	if [[ $TX -lt 1024 ]];then
	TX="${TX}B/s"
	elif [[ $TX -gt 1048576 ]];then
	TX=$(echo $TX | awk '{print $1/1048576 "MB/s"}')
	else
	TX=$(echo $TX | awk '{print $1/1024 "KB/s"}')
	fi
	  
	echo -e "$eth \t $RX   $TX "
	#printf "%s %s %s" "$eth" "$RX" "$TX"

}
